What penetrating oil do you recommend for freeing rusted parts? WD40 is next to useless and I can't get any heat to the parts which are frozen.

Plusgas.

slw

Any idea on availability, e.g. should I be able to get it at my local motor factors?

http://www1.mscdirect.com/PDF/2005/2629.pdf

any motor factor, agri engineering or bearing agent(BSL)will have a brand of release agent, even Halfords.

Thanks Trekster, but which is best?

it won't really matter which one you use, just use lots of it.

is the top of the thread visible/open for the stuff to get in there? Scrape off any rust you can with wire brush/tools to allow the penetrating oil to get in there.

If it's a vertical bolt/nut then you can build a ring of bluetak around the top to form a cup so you can fill it with the penetrating oil and leave it to soak in to the threaded section for a few hours rather than it running off.

Thanks for the responses.

They are both good.
We use Swantek at work(NB the Excellent acknowledgment on home page)
http://www.swantek.com/html/frames.htm
Soak, leave for 1/2hr and hey presto!!

All depends how rusty and what size your bolts/nuts, grade of steel are, sometimes nothing works unfortunately.

I've been using a product made by Wurth called 'Rost off ice'.

It is a release oil that has a freezing agent in it. When you spray it on it chills the bolt in order to shrink it a little. The idea is that this creates gap for the oil to penetrate the seized thread. It smells like the deep heat spray that footballers use.

Rost off

There are folks selling it on Ebay for less. It has been successful in releasing 95% of the seized fittings I've used it on in the last ten years or so. Like previously mentioned, sometimes it is just a lost cause.

If you can get your part into a bucket, then use diesel or even petrol- just be carefull

KT1973 – Member

If you can get your part into a bucket, then use diesel or even petrol- just be carefull
Good old fashioned farmers trick 😀

Like the sound of carrotcakes stuff(linky no worky, goes to amazon?)

Plusgas is great. It actually does what people think WD40 does, but doesn't. I've had a little success over the years with my stupidly powerful soldering gun- useless for soldering but it puts a fair amount of localised heat on, OK for small bolts. Freeze spray/chewing gum remover can sometimes he useful too.

As well as Wurth Rost Off there is
Loctite Freeze and Release http://loctitefreezeandrelease.com/

Ambersil Rust Flash
etc